2017 cat 299d2 serial FD202537 1780hrs Had an issue with the pre-filter clogging up previously, today I blew it out and didn't have any issues until it suddenly died backing up, a code popped up for fuel leakage which typically leads to low fuel rail pressure due to the HPFP not getting enough fuel. I plugged in cat ET and there is no fuel rail pressure. however there is a weird squeaking sound coming from the engine. See attached video. My guess is the HPFP died. Picture attached is when I was cranking. Thanks!
Update! The fuel pump isnt even spinning lol. I suppose I'll need to take the front case apart.
The idler gear holder broke?!?
This is the fuel pump being spun with a wrench. Should it be this difficult? https://youtube.com/shorts/hjE1tfGClGM?feature=share
And I found a broken tooth on the HPFP
picked up all new gears, a new pump, gaskets, filters and that bracket for the intermediate gear today. ($2828) I thought I had it figured out this morning in the shower... my thought was the pump gear had a tooth break off from poor manufacturing, wedged between the pump and the intermediate gear, bent the pump shaft and then broke the intermediate gear bracket.... but upon further inspection of the new pump... that shaft is like 1" in diameter. I highly doubt that's what happened.. Earlier that day I was having low rail pressure issues and found out the pre filter on the lift pump was packed with some sort of red particulates, not having a spare, I blew it out and reassembled. After that I ran a flow test on the lift pump and fount it to be supplying MUCH more fuel than it ever will need. I spoke with an old diesel tech in my area and he said he never fills up with any sort of biodiesel contaminated fuel... apparently it'll sit in these machines and get stale really fast. Since my machine only gets maybe 300 hours a year, this would line up. Before I install the new pump, I have an external 120v pump and filter system (5 micron) that I'm going to run tonight recycling the fuel through; along with some biocide to hopefully catch the all the junk in the tank since there is no way I can pull it for cleaning. Dump the fuel tomorrow and refill with good fresh fuel that has ZERO biodiesel in it, and always add some stanadyne additive to prevent this disaster from happening again. Wish me luck. -Hvguy
Holy cow! The red particles you found in the pre filter could've possibly been rust. Was there any water in the separator? Big thankyou for sharing such detail.
Nope. No water. Plastic tank with all stainless fittings. That's definitely some sorry of algae or..... Something. I've about got it back together. I put some red locktite on the pump nut and gave her hell while someone held the gear... Hoping it'll be enough. I'm about ready to pump the tank out and crank it. When I busted the gear off the old pump, I did notice the roll pin was smashed like the gear tried to rotate on the shaft, I'm guessing at this point the pump locked up, a tooth broke off the pump gear, broke the intermediate gear brackets and stopped. Since there's no core on the pump, I'll dissect it next week. Wish me luck.
Got everything installed, fuel additive added, fresh fuel, prime the system with all new filters, blow out all the lines, now it won't start at all. I have to go home and get my computer to see if it's even building pressure. Any ideas?
Well, when it's cranking, the return line from the fuel rail coming from the fuel pressure regulator is pouring fuel out of it, therefore it's not building enough pressure to inject. Also they conveniently don't sell the fuel pressure regulator separate from the fuel rail. a friend of mine mentioned I might have an issue with an injector returning way too much fuel and it will never build pressure, he mentioned to remove each one of the fuel lines and cap it off to see if the pump will build pressure pointing out that the issue is an injector that is stuck open, returning fuel. My money is on the bad fuel rail since I can't build over 86 psi cranking. Whoever put this curse on me, please stop, I learned my lesson whatever it is.
The plot thickens. I unplugged the high pressure side of the pump, and nothing comes out when cranking. I'm unplugging the battery and letting it sit. This makes no sense.
Checked power or anything dc coming to the top of the pump and there isn't any sort of signal. I guess my issue is up the line to the computer. Also when I was cranking I noticed the throttle said 0% even if I was moving the throttle knob. I'm at a loss
So, I verified the electronic device on top of the pump is definitely a solenoid and it's not getting power when cranking. So somehow the computer is at fault. Took the old one part of the way apart. It's just an element pump and spring like an old Detroit.
So I jumped 12v to the pump and got it running. Unfortunately it flagged a code for over pressure since I'm sure the pump was full stroke lol. But it does work however my computer is either not controlling it, or the wire is broken. Gonna dig through the service manual.
Upon further inspection, It appears the orange wire is ground, and the black or gray wire on the top of the pump is the signal.... the orange ground is also shared to the pressure regulator on the rail. The other line for the regulator or (press. relief drvr.) as its called, is pin 70. Im going to verify both grounds are connected to each other and then verify they all go back to the ECM. Attached is a schematic that outlines this.... im a little confused as to why they have 2 pins dedicated for ground and signal for the pump. also if anyone is trying to find that pump on the schematics, its called a supply pump
The boost pressure sensor and cam position sensor shown on your snip are both PWM sensors. They require an external power source (+5v) that is supplied by the ECM and a ground back to the ECM. The output signal from the sensor, also to the ECM, goes not surprisingly via the signal wire. However neither of those aforementioned sensors has anything directly to do with the signal from the ECM to the supply pump which is only via 2 wires.
I've verified that the ground and signal is making it to the computer on all pins. I guess the computer has died? Seems like and expensive fix just to find out. I did however manage to limp it out of the field with an external power supply. https://youtube.com/shorts/Hpr7_hbBzts?feature=share
That snip was a reference to what they call the fuel pump and it's associated wires. Any idea where I can get an ecm tested at lol. It's weird to not have any codes and the only thing not working is the pump signal wires.
The only thing that springs to mind is to install it on another identical machine and see what happens.
Please keep letting us know what you find as we all would like to know end causes and solutions. Thanks again. Simon C
The Systems Operation for your Tier4 final/Euro IV fuel system states: The valve is opened and closed by the ON/OFF of energizing the PCV [Pre-stroke Control Valve - fancy way of describing the fuel pump controller] , which is controlled by the Engine ECM. The ON/OFF timing is controlled based on signals from various sensors to provide optimal rail pressure. If you applied continuous current this explains why you got the "overpressurising" event. According to this description, you should be able to toggle your rigged-up external power source on and off to keep your fuel rail pressure in the 'happy' band. This probably isn't doing your brand new pump any good, but tell me... can you see the rail pressure responding to your 'toggling', if that makes sense? This could help identify a rail pressure sensor issue. Silly question... Is ET showing cranking speed while engine is cranking? See if you can verify both crankshaft AND camshaft speed sensor signals. While your in ET, spend 5 mins and check there's no crazy parameters for.... Troubleshooting these really sucks. There's nearly always guesswork involved since specifications seem to be highly classified due to emissions regulations... which leads me to think replacing the fuel rail is the better option (gives you a new rail pressure sensor and discharge valve, and is cheaper than an ECM). The fact that it runs when you apply external power is promising... could possibly rule out debris blocking your injectors if anything. I guess at this stage we're looking for any reason why the ECM would NOT command the fuel pump to 'pump'.
I'm confused too, but I'm sure there's some kind of logic involved. Before replacing the ECM I'd consider running some new wires externally. That would mean running four wires from the ECM and two wires to the pump, then joining them as per the schematic you modified and attached earlier. That would also involve running a new X985-E117 OR-20 wire to the pressure relief valve.
One more thing, your prime pump sounds good ticking away in your first video, has the sound changed? Hate for this to be something so simple. These have been problems for years.
UPDATE I took the whole machine down to the main cat store in houston to borrow one of their good ECM's for testing. Unfortunately this didnt help at all. It still didnt run. I no longer have the machine in my posession however i will hopefully have some updated info in the next week. Ill keep yall updated. @Chrisso Yes the pump was in good shape, I actually replaced it at the beginning of this year which lead me to find there is some junk in my tank that was clogging the fuel inlet hose. I blew it out with my truck air and kept on running. You can actually hear the change in the pumping noise when its getting clogged. And I verified about 5psi @ maybe 3gpm being supplied to the main HPFP.
No worries hvguy. Looking forward to the update... very keen to know what they find.
Ok, so the dealer said since I installed the pump out of time it messed it up... I don't believe this seeing as out of time wouldn't matter since it just wouldn't inject fuel. The way this injection system works is the pump works like an old element style pump, except instead of having a spiral spill port, that uses a solenoid to reduce flow by diverting the excess to the return port. They said I would have to replace my brand new pump with a brand new pump and it was going to be like $5,600, of which I don't have that much money. I opted to have them put it back together, I replaced the solenoid on the top that looked melted from earlier when I put too much power on it for too long, the machine now starts but it instantly dies. There are no codes, it builds fuel rail pressure, runs and instantly dies. I installed the old solenoid that was burned up and it works the same. Also while they were in there they installed a new product link antenna and harness, when I log into cat ET, I can see the product link but nothing is saved in it, no serial, no model no nothing. What is y'all's opinion. https://youtube.com/shorts/ShzhNTDutl0?feature=share
Do you have the right service manual for your machine? UENR0129 is what you should be using. States timing procedure and... Note: If a new supply pump is installed, a "Fuel Pump Calibration Override" must be performed using CAT Refer to Troubleshooting, UENR3423, "CAT ET Service Features, Fuel Pump Calibration". I'm still trying to work out why that pump is timed and if out-of-timing alone could damage the pump.
Interesting find. I do have the manual for it but didn't see that part. Wonder if they did that
Wow. What a mess. So when I originally dropped the machine off, I told them it had a new pump but I didn't time it. They instantly pulled my new pump and replaced it with a used but known good working pump in time. The called and said it needed a new pump; something about since I did set the timing it messed it up. I declined and wanted it put back together with my pump but set the timing. A week goes by and they call with it ready. I get there and the battery is dead? Whatever, hauled it home, charged it up and now it'll start but instantly die.... I spoke with a few other shops and figured it was worth the warranty to just get the machine fixed by cat. Fast-forward 3 weeks and they call me on a Wednesday saying it should be done that day. I don't receive any more calls until the next Monday saying they had an issue with the new pump.... It would start and then die yeah.... That's what it was doing when I dropped it off. Whatever. I drive down there to pick it up, had a little talk with the technician who did the replacement and he said the timing was 2 teeth off from whoever worked on it last (cat) so either 1. They fucked up and it was just an accident or 2. They sabotaged the timing to make me come back. Idk, either way I had a brand new pump I paid for sitting here. So it was shipped off to be tested and came back working. I asked them for a refund because they have been lying to me this whole time of which they declined.... So now they get to talk with visa. What an absolute disaster. For those who care, this is how that pump operates. It's setup like an old fashioned single element injection pump (imagine a p7100, but no spill port) the pump absolutely has to be in time with the crank and cam since it uses those 2 positions to control the electronic spill port on the pump to regulate pressure. It's pretty clever but also pretty dumb since they're the only ones that use this proprietary pump. If you check bobcat and Kubota v3800 engines. They also use something else. It's weird.
Sorry to hear, sounds like a disaster alright. Mind if I ask how you know this? Since your post about pump timing first came up I've been asking around too. A knowledgeable person explained to me that it has to do with controlling the "pulsing" and "pressure spikes" created by the high pressure fuel pump (30,000-odd psi). We're talking many fractions of a second but the goal is to make sure the spill port (in this case the Pre-stroke Control Valve) doesn't open at the exact moment an injector is injecting. This helps regulate combustion and keeps the penguins happy. I get the similarity between this pump and an older mechanical element pump in the fact that it uses an element to control discharge... but these common rail pumps first create pressure using a gerotor style feed pump (Cat calls it a Trochoid pump)... Once you get the high pressure created by the feed pump... the rest is up to the Pre-stroke Control Valve to simply control the amount of discharging... So the more I think about it, I can't really agree that it's anything like an older element style pump. Maybe someone more knowledgeable here can prove me wrong? Anyways, good discussion.
Before anyone comments, yes I know you can't have pressure without a restriction. I could've explained that a little better, but hope you get my drift. My main interest in this is trying to work out exactly HOW the engine ECM knows the pump timing is out (and thus shuts engine down after a second or two). This would go along way to proving the dealer wrong and you disputing the bill (or at least part of).